Approaches to Qualitative Comparative Analysis (QCA): A Systematic Review

The approach and method of Qualitative Comparative Analysis (QCA) have undergone remarkable developments since its launch in 1987 (Ragin 1987), in terms of dissemination, methodological innovation, and a diversification of approaches to QCA. At the same time, the use of QCA often lags behind methodological recommendations of good practice (Schneider and Wagemann 2010). This is a serious problem. Poor quality applications not only bear a high risk of flawed inferences, but also frequently raise harsh critiques of the QCA methodology as such. The recently introduced typology of approaches to QCA (Thomann and Maggetti 2017) outlines the (in)appropriateness of different analytic choices depending on a given approach, and urges users to apply QCA approaches consistently. However, no systematic knowledge exists as yet about the empirical prevalence of different types of approaches to QCA and whether they might be characterized by specific methodological problems. To address this gap, this paper performs a systematic review of 89 studies applying QCA in the field of Public Administration. Given its interdisciplinary nature and epistemological “affinity” toward some core assumptions of the QCA methodology, the field of Public Administration can be a regarded as a typical case of contemporary QCA use in social research. Our review addresses three questions. First, which types of QCA approaches prevail in Public Administration, and how prevalent are the more inconsistent “hybrids”? Second, are different approaches linked to particular good or not-so-good practices? Third, how have these phenomena evolved over time? We derive three expectations on this link. First, we expect that particularly the “hybrids” should display more methodological problems due to inconsistent analytic choices. Second, we expect some QCA approaches to meet the standards of good practices more consistently than other approaches, as these standards were developed for a specific type of QCA approach. Third, we expect that the standards of good practices have more frequently been met in more recent QCA applications, as the training and dissemination of such practices have considerably improved over time. This analysis provides the first empirical test of the usefulness of Thomann and Maggetti’s typology for describing and understanding the use of QCA. The results allow us to refine the standards of good practice for QCA in order to account for the prevalence of different QCA approaches. This information is important for users, reviewers, and teachers in order to move the use of QCA forward.